Nothing makes me notice things until I transcribe them.
This image comes from a death certificate in Mercer County, Illinois, which was analyzed in issue 3-30 of Casefile Clues. I've had the copy of this certificate for fifteen years at least and never noticed the file date was a year after Lucinda died.
I really don't think the delay is significant, but sometimes these things are. There was actually a find ($10) for filing a death late, but I'm uncertain whether the doctor had to pay the fine or not. I noted the difference in the dates in my analysis, but left it at that.
One should always look at file dates of documents as opposed to creation dates. If the gap is significant, determining the difference could be crucial to your research.
Or it could just be that the doctor was slow and lived a ways from the county seat.